OpenBSD-4.6/sys/nfs/nfs_syscalls.c
/* $OpenBSD: nfs_syscalls.c,v 1.82 2009/06/25 15:49:26 thib Exp $ */
/* $NetBSD: nfs_syscalls.c,v 1.19 1996/02/18 11:53:52 fvdl Exp $ */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rick Macklem at The University of Guelph.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)nfs_syscalls.c 8.5 (Berkeley) 3/30/95
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/namei.h>
#include <sys/syslog.h>
#include <sys/filedesc.h>
#include <sys/signalvar.h>
#include <sys/kthread.h>
#include <sys/queue.h>
#include <sys/syscallargs.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <nfs/xdr_subs.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nfsm_subs.h>
#include <nfs/nfsrvcache.h>
#include <nfs/nfsmount.h>
#include <nfs/nfsnode.h>
#include <nfs/nfs_var.h>
/* Global defs. */
extern int nfs_numasync;
extern struct nfsstats nfsstats;
extern int nfsrvw_procrastinate;
extern struct timeval nfsrvw_procrastinate_tv;
struct nfssvc_sock *nfs_udpsock;
int nfsd_waiting = 0;
#ifdef NFSSERVER
int nfsrv_getslp(struct nfsd *nfsd);
static int nfs_numnfsd = 0;
int (*nfsrv3_procs[NFS_NPROCS])(struct nfsrv_descript *,
struct nfssvc_sock *, struct proc *, struct mbuf **) = {
nfsrv_null,
nfsrv_getattr,
nfsrv_setattr,
nfsrv_lookup,
nfsrv3_access,
nfsrv_readlink,
nfsrv_read,
nfsrv_write,
nfsrv_create,
nfsrv_mkdir,
nfsrv_symlink,
nfsrv_mknod,
nfsrv_remove,
nfsrv_rmdir,
nfsrv_rename,
nfsrv_link,
nfsrv_readdir,
nfsrv_readdirplus,
nfsrv_statfs,
nfsrv_fsinfo,
nfsrv_pathconf,
nfsrv_commit,
nfsrv_noop
};
#endif
struct nfssvc_sockhead nfssvc_sockhead;
struct nfsdhead nfsd_head;
int nfssvc_sockhead_flag;
int nfsd_head_flag;
#ifdef NFSCLIENT
struct proc *nfs_asyncdaemon[NFS_MAXASYNCDAEMON];
int nfs_niothreads = -1;
#endif
/*
* NFS server pseudo system call for the nfsd's
* Based on the flag value it either:
* - adds a socket to the selection list
* - remains in the kernel as an nfsd
*/
int
sys_nfssvc(struct proc *p, void *v, register_t *retval)
{
int error = 0;
#ifdef NFSSERVER
struct sys_nfssvc_args /* {
syscallarg(int) flag;
syscallarg(caddr_t) argp;
} */ *uap = v;
int flags = SCARG(uap, flag);
struct file *fp;
struct mbuf *nam;
struct nfsd_args nfsdarg;
struct nfsd_srvargs nfsd_srvargs, *nsd = &nfsd_srvargs;
struct nfsd *nfsd;
#endif
/* Must be super user */
error = suser(p, 0);
if (error)
return (error);
#ifndef NFSSERVER
error = ENOSYS;
#else
while (nfssvc_sockhead_flag & SLP_INIT) {
nfssvc_sockhead_flag |= SLP_WANTINIT;
tsleep(&nfssvc_sockhead, PSOCK, "nfsd init", 0);
}
switch (flags) {
case NFSSVC_ADDSOCK:
error = copyin(SCARG(uap, argp), &nfsdarg, sizeof(nfsdarg));
if (error)
return (error);
error = getsock(p->p_fd, nfsdarg.sock, &fp);
if (error)
return (error);
/*
* Get the client address for connected sockets.
*/
if (nfsdarg.name == NULL || nfsdarg.namelen == 0)
nam = NULL;
else {
error = sockargs(&nam, nfsdarg.name, nfsdarg.namelen,
MT_SONAME);
if (error) {
FRELE(fp);
return (error);
}
}
error = nfssvc_addsock(fp, nam);
FRELE(fp);
break;
case NFSSVC_NFSD:
error = copyin(SCARG(uap, argp), nsd, sizeof(*nsd));
if (error)
return (error);
nfsd = malloc(sizeof(*nfsd), M_NFSD, M_WAITOK|M_ZERO);
nfsd->nfsd_procp = p;
nfsd->nfsd_slp = NULL;
error = nfssvc_nfsd(nfsd);
break;
default:
error = EINVAL;
break;
}
if (error == EINTR || error == ERESTART)
error = 0;
#endif /* !NFSSERVER */
return (error);
}
#ifdef NFSSERVER
/*
* Adds a socket to the list for servicing by nfsds.
*/
int
nfssvc_addsock(fp, mynam)
struct file *fp;
struct mbuf *mynam;
{
struct mbuf *m;
int siz;
struct nfssvc_sock *slp;
struct socket *so;
struct nfssvc_sock *tslp;
int error, s;
so = (struct socket *)fp->f_data;
tslp = (struct nfssvc_sock *)0;
/*
* Add it to the list, as required.
*/
if (so->so_proto->pr_protocol == IPPROTO_UDP) {
tslp = nfs_udpsock;
if (tslp->ns_flag & SLP_VALID) {
m_freem(mynam);
return (EPERM);
}
}
if (so->so_type == SOCK_STREAM)
siz = NFS_MAXPACKET + sizeof (u_long);
else
siz = NFS_MAXPACKET;
error = soreserve(so, siz, siz);
if (error) {
m_freem(mynam);
return (error);
}
/*
* Set protocol specific options { for now TCP only } and
* reserve some space. For datagram sockets, this can get called
* repeatedly for the same socket, but that isn't harmful.
*/
if (so->so_type == SOCK_STREAM) {
MGET(m, M_WAIT, MT_SOOPTS);
*mtod(m, int32_t *) = 1;
m->m_len = sizeof(int32_t);
sosetopt(so, SOL_SOCKET, SO_KEEPALIVE, m);
}
if (so->so_proto->pr_domain->dom_family == AF_INET &&
so->so_proto->pr_protocol == IPPROTO_TCP) {
MGET(m, M_WAIT, MT_SOOPTS);
*mtod(m, int32_t *) = 1;
m->m_len = sizeof(int32_t);
sosetopt(so, IPPROTO_TCP, TCP_NODELAY, m);
}
so->so_rcv.sb_flags &= ~SB_NOINTR;
so->so_rcv.sb_timeo = 0;
so->so_snd.sb_flags &= ~SB_NOINTR;
so->so_snd.sb_timeo = 0;
if (tslp)
slp = tslp;
else {
slp = malloc(sizeof(struct nfssvc_sock), M_NFSSVC,
M_WAITOK|M_ZERO);
TAILQ_INSERT_TAIL(&nfssvc_sockhead, slp, ns_chain);
}
slp->ns_so = so;
slp->ns_nam = mynam;
fp->f_count++;
slp->ns_fp = fp;
s = splsoftnet();
so->so_upcallarg = (caddr_t)slp;
so->so_upcall = nfsrv_rcv;
slp->ns_flag = (SLP_VALID | SLP_NEEDQ);
nfsrv_wakenfsd(slp);
splx(s);
return (0);
}
/*
* Called by nfssvc() for nfsds. Just loops around servicing rpc requests
* until it is killed by a signal.
*/
int
nfssvc_nfsd(struct nfsd *nfsd)
{
struct mbuf *m;
int siz;
struct nfssvc_sock *slp;
struct socket *so;
int *solockp;
struct nfsrv_descript *nd = NULL;
struct mbuf *mreq;
int error = 0, cacherep, s, sotype, writes_todo;
struct timeval tv;
cacherep = RC_DOIT;
writes_todo = 0;
s = splsoftnet();
TAILQ_INSERT_TAIL(&nfsd_head, nfsd, nfsd_chain);
nfs_numnfsd++;
/*
* Loop getting rpc requests until SIGKILL.
*/
for (;;) {
if ((nfsd->nfsd_flag & NFSD_REQINPROG) == 0) {
/* attach an nfssvc_sock to nfsd */
error = nfsrv_getslp(nfsd);
if (error)
goto done;
slp = nfsd->nfsd_slp;
if (slp->ns_flag & SLP_VALID) {
if (slp->ns_flag & SLP_DISCONN)
nfsrv_zapsock(slp);
else if (slp->ns_flag & SLP_NEEDQ) {
slp->ns_flag &= ~SLP_NEEDQ;
(void) nfs_sndlock(&slp->ns_solock,
(struct nfsreq *)0);
nfsrv_rcv(slp->ns_so, (caddr_t)slp,
M_WAIT);
nfs_sndunlock(&slp->ns_solock);
}
error = nfsrv_dorec(slp, nfsd, &nd);
getmicrotime(&tv);
if (error && LIST_FIRST(&slp->ns_tq) &&
timercmp(&LIST_FIRST(&slp->ns_tq)->nd_time,
&tv, <=)) {
error = 0;
cacherep = RC_DOIT;
writes_todo = 1;
} else
writes_todo = 0;
nfsd->nfsd_flag |= NFSD_REQINPROG;
}
} else {
error = 0;
slp = nfsd->nfsd_slp;
}
if (error || (slp->ns_flag & SLP_VALID) == 0) {
if (nd) {
free((caddr_t)nd, M_NFSRVDESC);
nd = NULL;
}
nfsd->nfsd_slp = (struct nfssvc_sock *)0;
nfsd->nfsd_flag &= ~NFSD_REQINPROG;
nfsrv_slpderef(slp);
continue;
}
splx(s);
so = slp->ns_so;
sotype = so->so_type;
if (so->so_proto->pr_flags & PR_CONNREQUIRED)
solockp = &slp->ns_solock;
else
solockp = (int *)0;
if (nd) {
if (nd->nd_nam2)
nd->nd_nam = nd->nd_nam2;
else
nd->nd_nam = slp->ns_nam;
cacherep = nfsrv_getcache(nd, slp, &mreq);
}
/*
* Loop to get all the write rpc relies that have been
* gathered together.
*/
do {
switch (cacherep) {
case RC_DOIT:
if (writes_todo || (!(nd->nd_flag & ND_NFSV3) &&
nd->nd_procnum == NFSPROC_WRITE &&
nfsrvw_procrastinate > 0))
error = nfsrv_writegather(&nd, slp,
nfsd->nfsd_procp, &mreq);
else
error = (*(nfsrv3_procs[nd->nd_procnum]))(nd,
slp, nfsd->nfsd_procp, &mreq);
if (mreq == NULL) {
if (nd != NULL) {
m_freem(nd->nd_nam2);
m_freem(nd->nd_mrep);
}
break;
}
if (error) {
nfsstats.srv_errs++;
nfsrv_updatecache(nd, 0, mreq);
if (nd->nd_nam2)
m_freem(nd->nd_nam2);
break;
}
nfsstats.srvrpccnt[nd->nd_procnum]++;
nfsrv_updatecache(nd, 1, mreq);
nd->nd_mrep = (struct mbuf *)0;
/* FALLTHROUGH */
case RC_REPLY:
m = mreq;
siz = 0;
while (m) {
siz += m->m_len;
m = m->m_next;
}
if (siz <= 0 || siz > NFS_MAXPACKET) {
printf("mbuf siz=%d\n",siz);
panic("Bad nfs svc reply");
}
m = mreq;
m->m_pkthdr.len = siz;
m->m_pkthdr.rcvif = (struct ifnet *)0;
/*
* For stream protocols, prepend a Sun RPC
* Record Mark.
*/
if (sotype == SOCK_STREAM) {
M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
*mtod(m, u_int32_t *) = htonl(0x80000000 | siz);
}
if (solockp)
(void) nfs_sndlock(solockp, (struct nfsreq *)0);
if (slp->ns_flag & SLP_VALID)
error = nfs_send(so, nd->nd_nam2, m, NULL);
else {
error = EPIPE;
m_freem(m);
}
if (nd->nd_nam2)
m_freem(nd->nd_nam2);
if (nd->nd_mrep)
m_freem(nd->nd_mrep);
if (error == EPIPE)
nfsrv_zapsock(slp);
if (solockp)
nfs_sndunlock(solockp);
if (error == EINTR || error == ERESTART) {
free((caddr_t)nd, M_NFSRVDESC);
nfsrv_slpderef(slp);
s = splsoftnet();
goto done;
}
break;
case RC_DROPIT:
m_freem(nd->nd_mrep);
m_freem(nd->nd_nam2);
break;
};
if (nd) {
free(nd, M_NFSRVDESC);
nd = NULL;
}
/*
* Check to see if there are outstanding writes that
* need to be serviced.
*/
getmicrotime(&tv);
s = splsoftclock();
if (LIST_FIRST(&slp->ns_tq) &&
timercmp(&LIST_FIRST(&slp->ns_tq)->nd_time, &tv, <=)) {
cacherep = RC_DOIT;
writes_todo = 1;
} else
writes_todo = 0;
splx(s);
} while (writes_todo);
s = splsoftnet();
if (nfsrv_dorec(slp, nfsd, &nd)) {
nfsd->nfsd_flag &= ~NFSD_REQINPROG;
nfsd->nfsd_slp = NULL;
nfsrv_slpderef(slp);
}
}
done:
TAILQ_REMOVE(&nfsd_head, nfsd, nfsd_chain);
splx(s);
free((caddr_t)nfsd, M_NFSD);
if (--nfs_numnfsd == 0)
nfsrv_init(1); /* Reinitialize everything */
return (error);
}
/*
* Shut down a socket associated with an nfssvc_sock structure.
* Should be called with the send lock set, if required.
* The trick here is to increment the sref at the start, so that the nfsds
* will stop using it and clear ns_flag at the end so that it will not be
* reassigned during cleanup.
*/
void
nfsrv_zapsock(slp)
struct nfssvc_sock *slp;
{
struct nfsrv_descript *nwp, *nnwp;
struct socket *so;
struct file *fp;
struct mbuf *m, *n;
int s;
slp->ns_flag &= ~SLP_ALLFLAGS;
fp = slp->ns_fp;
if (fp) {
FREF(fp);
slp->ns_fp = NULL;
so = slp->ns_so;
so->so_upcall = NULL;
soshutdown(so, SHUT_RDWR);
closef(fp, NULL);
if (slp->ns_nam)
MFREE(slp->ns_nam, m);
m_freem(slp->ns_raw);
m = slp->ns_rec;
while (m) {
n = m->m_nextpkt;
m_freem(m);
m = n;
}
s = splsoftclock();
for (nwp = LIST_FIRST(&slp->ns_tq); nwp != NULL; nwp = nnwp) {
nnwp = LIST_NEXT(nwp, nd_tq);
LIST_REMOVE(nwp, nd_tq);
free((caddr_t)nwp, M_NFSRVDESC);
}
LIST_INIT(&slp->ns_tq);
splx(s);
}
}
/*
* Derefence a server socket structure. If it has no more references and
* is no longer valid, you can throw it away.
*/
void
nfsrv_slpderef(slp)
struct nfssvc_sock *slp;
{
if (--(slp->ns_sref) == 0 && (slp->ns_flag & SLP_VALID) == 0) {
TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
free((caddr_t)slp, M_NFSSVC);
}
}
/*
* Initialize the data structures for the server.
* Handshake with any new nfsds starting up to avoid any chance of
* corruption.
*/
void
nfsrv_init(terminating)
int terminating;
{
struct nfssvc_sock *slp, *nslp;
if (nfssvc_sockhead_flag & SLP_INIT)
panic("nfsd init");
nfssvc_sockhead_flag |= SLP_INIT;
if (terminating) {
for (slp = TAILQ_FIRST(&nfssvc_sockhead); slp != NULL;
slp = nslp) {
nslp = TAILQ_NEXT(slp, ns_chain);
if (slp->ns_flag & SLP_VALID)
nfsrv_zapsock(slp);
TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
free((caddr_t)slp, M_NFSSVC);
}
nfsrv_cleancache(); /* And clear out server cache */
}
TAILQ_INIT(&nfssvc_sockhead);
nfssvc_sockhead_flag &= ~SLP_INIT;
if (nfssvc_sockhead_flag & SLP_WANTINIT) {
nfssvc_sockhead_flag &= ~SLP_WANTINIT;
wakeup((caddr_t)&nfssvc_sockhead);
}
TAILQ_INIT(&nfsd_head);
nfsd_head_flag &= ~NFSD_CHECKSLP;
nfs_udpsock = malloc(sizeof(struct nfssvc_sock), M_NFSSVC,
M_WAITOK|M_ZERO);
TAILQ_INSERT_HEAD(&nfssvc_sockhead, nfs_udpsock, ns_chain);
}
#endif /* NFSSERVER */
#ifdef NFSCLIENT
/*
* Asynchronous I/O threads for client nfs.
* They do read-ahead and write-behind operations on the block I/O cache.
* Never returns unless it fails or gets killed.
*/
void
nfssvc_iod(void *arg)
{
struct proc *p = (struct proc *)arg;
struct buf *bp, *nbp;
int i, myiod;
struct vnode *vp;
int error = 0, s, bufcount;
bufcount = 256; /* XXX: Big enough? sysctl, constant ? */
/* Assign my position or return error if too many already running. */
myiod = -1;
for (i = 0; i < NFS_MAXASYNCDAEMON; i++) {
if (nfs_asyncdaemon[i] == NULL) {
myiod = i;
break;
}
}
if (myiod == -1)
kthread_exit(EBUSY);
nfs_asyncdaemon[myiod] = p;
nfs_numasync++;
/* Upper limit on how many bufs we'll queue up for this iod. */
if (nfs_bufqmax > bcstats.numbufs / 4) {
nfs_bufqmax = bcstats.numbufs / 4; /* limit to 1/4 of bufs */
bufcount = 0;
}
nfs_bufqmax += bufcount;
/* Just loop around doin our stuff until SIGKILL. */
for (;;) {
while (TAILQ_FIRST(&nfs_bufq) == NULL && error == 0) {
error = tsleep(&nfs_bufq,
PWAIT | PCATCH, "nfsidl", 0);
}
while ((bp = TAILQ_FIRST(&nfs_bufq)) != NULL) {
/* Take one off the front of the list */
TAILQ_REMOVE(&nfs_bufq, bp, b_freelist);
nfs_bufqlen--;
if (bp->b_flags & B_READ)
(void) nfs_doio(bp, NULL);
else do {
/*
* Look for a delayed write for the same vnode, so I can do
* it now. We must grab it before calling nfs_doio() to
* avoid any risk of the vnode getting vclean()'d while
* we are doing the write rpc.
*/
vp = bp->b_vp;
s = splbio();
LIST_FOREACH(nbp, &vp->v_dirtyblkhd, b_vnbufs) {
if ((nbp->b_flags &
(B_BUSY|B_DELWRI|B_NEEDCOMMIT|B_NOCACHE))!=B_DELWRI)
continue;
nbp->b_flags |= B_ASYNC;
bremfree(nbp);
buf_acquire(nbp);
break;
}
/*
* For the delayed write, do the first part of nfs_bwrite()
* up to, but not including nfs_strategy().
*/
if (nbp) {
nbp->b_flags &= ~(B_READ|B_DONE|B_ERROR);
buf_undirty(nbp);
nbp->b_vp->v_numoutput++;
}
splx(s);
(void) nfs_doio(bp, NULL);
} while ((bp = nbp) != NULL);
}
if (error) {
nfs_asyncdaemon[myiod] = NULL;
nfs_numasync--;
nfs_bufqmax -= bufcount;
kthread_exit(error);
}
}
}
void
nfs_getset_niothreads(set)
int set;
{
struct proc *p;
int i, have, start;
for (have = 0, i = 0; i < NFS_MAXASYNCDAEMON; i++)
if (nfs_asyncdaemon[i] != NULL)
have++;
if (set) {
/* clamp to sane range */
nfs_niothreads = max(0, min(nfs_niothreads, NFS_MAXASYNCDAEMON));
start = nfs_niothreads - have;
while (start > 0) {
kthread_create(nfssvc_iod, p, &p, "nfsio");
start--;
}
for (i = 0; (start < 0) && (i < NFS_MAXASYNCDAEMON); i++)
if (nfs_asyncdaemon[i] != NULL) {
psignal(nfs_asyncdaemon[i], SIGKILL);
start++;
}
} else {
if (nfs_niothreads >= 0)
nfs_niothreads = have;
}
}
#endif /* NFSCLIENT */
#ifdef NFSSERVER
/*
* Find an nfssrv_sock for nfsd, sleeping if needed.
*/
int
nfsrv_getslp(struct nfsd *nfsd)
{
struct nfssvc_sock *slp;
int error;
again:
while (nfsd->nfsd_slp == NULL &&
(nfsd_head_flag & NFSD_CHECKSLP) == 0) {
nfsd->nfsd_flag |= NFSD_WAITING;
nfsd_waiting++;
error = tsleep(nfsd, PSOCK | PCATCH, "nfsd", 0);
nfsd_waiting--;
if (error)
return (error);
}
if (nfsd->nfsd_slp == NULL &&
(nfsd_head_flag & NFSD_CHECKSLP) != 0) {
TAILQ_FOREACH(slp, &nfssvc_sockhead, ns_chain) {
if ((slp->ns_flag & (SLP_VALID | SLP_DOREC)) ==
(SLP_VALID | SLP_DOREC)) {
slp->ns_flag &= ~SLP_DOREC;
slp->ns_sref++;
nfsd->nfsd_slp = slp;
break;
}
}
if (slp == NULL)
nfsd_head_flag &= ~NFSD_CHECKSLP;
}
if (nfsd->nfsd_slp == NULL)
goto again;
return (0);
}
#endif /* NFSSERVER */